Differential transcriptional activation by Oct-1 and Oct-2: interdependent activation domains induce Oct-2 phosphorylation.
The ubiquitous Oct-1 and lymphoid Oct-2 POU homeodomain transcription factors bind to the same DNA sequence but differ in their activation potential. Oct-2 is a positive, negative, or neutral regulator of beta-globin transcription depending on the position and sequence of multimerized binding sites. To activate transcription, Oct-2 relies on two interdependent nonacidic domains, an N-terminal glutamine-rich region and a C-terminal serine-, threonine-, and proline-rich region. Oct-1 also contains a functional glutamine-rich region but fails to activate beta-globin transcription in our assay because the Oct-1 C-terminus is inactive, indicating that differential activation by Oct-1 and Oct-2 is determined by the combination of multiple activation domains. Oct-2 displays a unique phosphorylation pattern that is absent from molecules lacking one or the other activation domain, suggesting the activation domains have a role in inducing protein phosphorylation.
Tanaka
M
M
Cold Spring Harbor Laboratory, New York 11724.
Herr
W
W
D000595:Amino Acid Sequence; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D005914:Globins / Q000235:genetics*; D006367:HeLa Cells / Q000378:metabolism; D051863:Host Cell Factor C1; D006801:Humans; D008969:Molecular Sequence Data; D050811:Octamer Transcription Factor-1; D050813:Octamer Transcription Factor-2; D015345:Oligonucleotide Probes; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation
D004268:DNA-Binding Proteins; C497692:HCFC1 protein, human; D051863:Host Cell Factor C1; D050811:Octamer Transcription Factor-1; D050813:Octamer Transcription Factor-2; D015345:Oligonucleotide Probes; C494165:POU2F1 protein, human; C058435:POU2F2 protein, human; D014157:Transcription Factors; D005914:Globins